diff --git a/reference/ftp/functions/ftp-pasv.xml b/reference/ftp/functions/ftp-pasv.xml
index 8150771fe4..87a610140d 100644
--- a/reference/ftp/functions/ftp-pasv.xml
+++ b/reference/ftp/functions/ftp-pasv.xml
@@ -1,5 +1,5 @@
 <?xml version="1.0" encoding="iso-8859-1"?>
-<!-- $Revision: 1.8 $ -->
+<!-- $Revision: 1.9 $ -->
 <refentry xml:id="function.ftp-pasv" xmlns="http://docbook.org/ns/docbook">
  <refnamediv>
   <refname>ftp_pasv</refname>
@@ -18,6 +18,10 @@
    rather than by the server.
    It may be needed if the client is behind firewall.
   </para>
+  <para>
+   Please note that <function>ftp_pasv</function> can only be called after a
+   successfull login or otherwise it will fail.
+  </para>
  </refsect1>
  <refsect1 role="parameters">
   &reftitle.parameters;